Neoadjuvant chemotherapy in patients ≥70 with node-positive triple negative breast cancer

Background: Neoadjuvant chemotherapy (NAC) is less frequently administered in patients > 70 years with triple negative breast cancer (TNBC) due to age-related comorbidity and fragility concerns. This study assesses trends and clinical benefit of NAC among clinically node-positive (cN+) patients. Methods: We identified females ≥ 70 in the National Cancer Database with cN+ nonmetastatic TNBC who underwent surgery from 2012 to 2021. Surgical approach, pathologic tumor and nodal stage, trends in NAC use, and rates of pathologic complete response (pCR) were used to assess the benefit of NAC. Results: Of 4598 patients, 2377 (51.7 %) received NAC, 1210 (26.3 %) received adjuvant chemotherapy alone (AC), and 1101 (22.0 %) received no chemotherapy. Rates of NAC increased from 29 % to 75 % (p < 0.001). NAC was more common in younger patients with larger tumors and those treated at academic institutions (p < 0.05). NAC patients were more likely to avoid axillary lymph node dissection (31 %, AC: 18 %, none: 15 %, p < 0.001). Among NAC patients, 22 % had no response to NAC, 32 % a breast pCR, 46 % nodal a pCR and 25 % pCR in both. 7 % of patients had breast pCR but remained pN+ . Overall survival (OS) did not differ between NAC and AC patients but was better than those without chemotherapy (107.6 vs. 98.2 vs. 32.6 months, respectively). Achieving breast, axillary, or total pCR was associated with improved OS in NAC patients. Conclusion: While specific chemotherapy regimens, dose reductions, and adverse events were unable to be evaluated, clinically fit patients should be counseled on NAC as an option given the potential for clinical benefit.